Mayweed chamomile reproduces by seeds. Plants of average size are capable of producing from 5000 to 17,000 seeds. This plant is a weed of disturbed soils and may be an indicated of loamy soils. Seeds germinate mainly in the autumn and spring, but some germination can occur throughout the year. Seeds can remain over 50% viable in the soil for more than 11 years.
Mayweed chamomile is frost-hardy at the rosette stage and may grow as a winter annual. It is moderately drought-resistant, and summer drought may restrict the size of the plant, but does not prevent seed development. Once the mayweed becomes established, eradication is impossible. Mayweed chamomile is a serious problem in cereal crops, waste areas, pastures, and along roadsides. Contact with mayweed can cause skin rashes and irritation to the mucous membranes of livestock.
Combinations of rotation grazing and herbicides treatments are the best methods of successful control of mayweed chamomile in pastures.
It is most important to prevent the production and spread of mayweed chamomile seed. Seed is dispersed by water in ditches and streams, in contaminated crop seed, and by animals or equipment. Prevent seed production whenever possible; sow clean seed, manage animal movement to avoid infested areas, and clean equipment whenever it is moved from infested to uninfested areas. Agricultural seed, hay, and livestock feeds may become contaminated with mayweed chamomile seed. Always select and use certified weed-free forage, feed, and seed to prevent reinfestation of an area. Quarantine livestock known to have been in areas infested with mayweed chamomile. It may be necessary to clean the animals’ coats before they are moved to un-infested land.